Elementary Techniques for Erdős–Ko–Rado-like Theorems
نویسندگان
چکیده
The well-known Erdős–Ko–Rado Theorem states that if F is a family of k-element subsets of {1, 2, . . . , n} (n ≥ 2k) satisfying S, T ∈ F ⇒ |S ∩ T | ≥ 1, then |F| ≤ ( n−1 k−1 ) . The theorem also provides necessary and sufficient conditions for attaining the maximum. We present elementary methods for deriving generalizations of the Erdős– Ko–Rado Theorem on several classes of combinatorial objects. We also extend our results to systems under Hamming intersection.
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تاریخ انتشار 2008